Lipid metabolism Flashcards
How are lipids broken down?
Broken in to micelles in small intestine, absorbed as chylomicrons
Name chylomicron packages
VLDL, LDL, IDL, HDL
How do chylomicrons get in to adipocytes?
Insulin binds to receptors and activates GLUT4 which allows chylomicrons, glucose and short chain fatty acids across membrane
Where does synthesis of TAG occur?
Cytoplasm only
What is committed step of FA synthesis?
Acetyl CoA Acetyl CoA carboxylase to Malonyl CoA -> fatty acid chain
What stimulates Acetyl CoA Carboxylase?
Citrate, INsulin
Ibhibited by AMP, Glucagon, Epi
Where are fatty acids activated to be targeted by B-oxidation?
Cytosol
Where does B-oxidation occur?
Inner mitochondrial matrix
When does B-oxidation run at a high rate?
When glucose is low
Name the fatty acid chains released from TAG to get glycerol backbone
TAG -> Dag -> Mag
How many carbons are cleaved at a time during B-oxidation?
2 carbons at a time to release an Acetyl CoA
How do fatty acids get in to mitochondria?
Faty acid activated to Fatty Acyl-SCoA
Fatty acyl SCoA uses Carnitine Transferase -> Fatty Acid Carnitine (inner membrane)CoA -> Fatty Acyl CoA (in Mitochondrial matrix)
How many Acetyl CoAs come from a 16 carbon fatty acid?
8
What does fat burns in the flame of carbs mean?
To use acetyl CoA as energy must have glucose
One round of B-oxidation forms what 3 molecules?
1 Acetyl CoA, 1 FADH2, 1 NADH
